There is a high prevalence (60-88 percent) of cigarette smoking among people with schizophrenia, but few smoking cessation interventions have been developed for these patients. Little is known about factors that control smoking in this population or whether interventions that reduce cigarette smoking among the general population are effective in smokers with schizophrenia. Two pharmacotherapies that reduce smoking in the general population are transdermal nicotine and sustained release bupropion. Because of neurochemical dysfunction associated with schizophrenia, these pharmacotherapies may be less effective in smokers with schizophrenia. Clinical and experimental studies on the effects of nicotine replacement in smokers with schizophrenia have yielded equivocal results. Preliminary results from a single treatment study with sustained release bupropion appear promising. The studies in the present proposal are designed to examine under controlled laboratory conditions the effects of transdermal nicotine (0, 21, 42 mg/day) and sustained release bupropion (0, 150, 300 mg/day) on smoking in people with schizophrenia and non-schizophrenic controls. The effects of transdermal nicotine and sustained release bupropion on smoking topography measures, smoking urges, nicotine withdrawal symptoms and affect will be determined. These studies use within-subjects, repeated measures, placebo controlled designs. Together, they will provide much-needed information on the biological, behavioral and subjective effects of transdermal nicotine and sustained release bupropion on smoking in people with schizophrenia. In turn, this information could contribute to the development of effective smoking cessation treatments for smokers with schizophrenia.